This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

4to6

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Revision as of 19:38, 11 August 2016

Structure basis of cellular dNTP regulation, SAMHD1-dGTP-dATP-dTTP/dGTP complex

Structural highlights

4to6 is a 4 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, , ,
Related:	4tnp, 4tnr, 4tnq, 4tnx, 4tny, 4tnz, 4to0, 4to1, 4to2, 4to3, 4to4, 4to5
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Disease

[SAMH1_HUMAN] Defects in SAMHD1 are the cause of Aicardi-Goutieres syndrome type 5 (AGS5) [MIM:612952]. A form of Aicardi-Goutieres syndrome, a genetically heterogeneous disease characterized by cerebral atrophy, leukoencephalopathy, intracranial calcifications, chronic cerebrospinal fluid (CSF) lymphocytosis, increased CSF alpha-interferon, and negative serologic investigations for common prenatal infection. Clinical features as thrombocytopenia, hepatosplenomegaly and elevated hepatic transaminases along with intermittent fever may erroneously suggest an infective process. Severe neurological dysfunctions manifest in infancy as progressive microcephaly, spasticity, dystonic posturing and profound psychomotor retardation. Death often occurs in early childhood.^[1] ^[2] Defects in SAMHD1 are the cause of chilblain lupus type 2 (CHBL2) [MIM:614415]. A rare cutaneous form of lupus erythematosus. Affected individuals present with painful bluish-red papular or nodular lesions of the skin in acral locations precipitated by cold and wet exposure at temperatures less than 10 degrees centigrade.^[3]

Function

[SAMH1_HUMAN] Putative nuclease involved in innate immune response by acting as a negative regulator of the cell-intrinsic antiviral response. May play a role in mediating proinflammatory responses to TNF-alpha signaling.^[4] ^[5]

Publication Abstract from PubMed

The sterile alpha motif and HD domain-containing protein 1 (SAMHD1), a dNTPase, prevents the infection of nondividing cells by retroviruses, including HIV, by depleting the cellular dNTP pool available for viral reverse transcription. SAMHD1 is a major regulator of cellular dNTP levels in mammalian cells. Mutations in SAMHD1 are associated with chronic lymphocytic leukemia (CLL) and the autoimmune condition Aicardi Goutieres syndrome (AGS). The dNTPase activity of SAMHD1 can be regulated by dGTP, with which SAMHD1 assembles into catalytically active tetramers. Here we present extensive biochemical and structural data that reveal an exquisite activation mechanism of SAMHD1 via combined action of both GTP and dNTPs. We obtained 26 crystal structures of SAMHD1 in complex with different combinations of GTP and dNTP mixtures, which depict the full spectrum of GTP/dNTP binding at the eight allosteric and four catalytic sites of the SAMHD1 tetramer. Our data demonstrate how SAMHD1 is activated by binding of GTP or dGTP at allosteric site 1 and a dNTP of any type at allosteric site 2. Our enzymatic assays further reveal a robust regulatory mechanism of SAMHD1 activity, which bares resemblance to that of the ribonuclease reductase responsible for cellular dNTP production. These results establish a complete framework for a mechanistic understanding of the important functions of SAMHD1 in the regulation of cellular dNTP levels, as well as in HIV restriction and the pathogenesis of CLL and AGS.

Structural basis of cellular dNTP regulation by SAMHD1.,Ji X, Tang C, Zhao Q, Wang W, Xiong Y Proc Natl Acad Sci U S A. 2014 Oct 14;111(41):E4305-14. doi:, 10.1073/pnas.1412289111. Epub 2014 Sep 29. PMID:25267621^[6]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Rice GI, Bond J, Asipu A, Brunette RL, Manfield IW, Carr IM, Fuller JC, Jackson RM, Lamb T, Briggs TA, Ali M, Gornall H, Couthard LR, Aeby A, Attard-Montalto SP, Bertini E, Bodemer C, Brockmann K, Brueton LA, Corry PC, Desguerre I, Fazzi E, Cazorla AG, Gener B, Hamel BC, Heiberg A, Hunter M, van der Knaap MS, Kumar R, Lagae L, Landrieu PG, Lourenco CM, Marom D, McDermott MF, van der Merwe W, Orcesi S, Prendiville JS, Rasmussen M, Shalev SA, Soler DM, Shinawi M, Spiegel R, Tan TY, Vanderver A, Wakeling EL, Wassmer E, Whittaker E, Lebon P, Stetson DB, Bonthron DT, Crow YJ. Mutations involved in Aicardi-Goutieres syndrome implicate SAMHD1 as regulator of the innate immune response. Nat Genet. 2009 Jul;41(7):829-32. doi: 10.1038/ng.373. Epub 2009 Jun 14. PMID:19525956 doi:10.1038/ng.373
↑ Thiele H, du Moulin M, Barczyk K, George C, Schwindt W, Nurnberg G, Frosch M, Kurlemann G, Roth J, Nurnberg P, Rutsch F. Cerebral arterial stenoses and stroke: novel features of Aicardi-Goutieres syndrome caused by the Arg164X mutation in SAMHD1 are associated with altered cytokine expression. Hum Mutat. 2010 Nov;31(11):E1836-50. doi: 10.1002/humu.21357. PMID:20842748 doi:10.1002/humu.21357
↑ Ravenscroft JC, Suri M, Rice GI, Szynkiewicz M, Crow YJ. Autosomal dominant inheritance of a heterozygous mutation in SAMHD1 causing familial chilblain lupus. Am J Med Genet A. 2011 Jan;155A(1):235-7. doi: 10.1002/ajmg.a.33778. PMID:21204240 doi:10.1002/ajmg.a.33778
↑ Liao W, Bao Z, Cheng C, Mok YK, Wong WS. Dendritic cell-derived interferon-gamma-induced protein mediates tumor necrosis factor-alpha stimulation of human lung fibroblasts. Proteomics. 2008 Jul;8(13):2640-50. doi: 10.1002/pmic.200700954. PMID:18546154 doi:10.1002/pmic.200700954
↑ Rice GI, Bond J, Asipu A, Brunette RL, Manfield IW, Carr IM, Fuller JC, Jackson RM, Lamb T, Briggs TA, Ali M, Gornall H, Couthard LR, Aeby A, Attard-Montalto SP, Bertini E, Bodemer C, Brockmann K, Brueton LA, Corry PC, Desguerre I, Fazzi E, Cazorla AG, Gener B, Hamel BC, Heiberg A, Hunter M, van der Knaap MS, Kumar R, Lagae L, Landrieu PG, Lourenco CM, Marom D, McDermott MF, van der Merwe W, Orcesi S, Prendiville JS, Rasmussen M, Shalev SA, Soler DM, Shinawi M, Spiegel R, Tan TY, Vanderver A, Wakeling EL, Wassmer E, Whittaker E, Lebon P, Stetson DB, Bonthron DT, Crow YJ. Mutations involved in Aicardi-Goutieres syndrome implicate SAMHD1 as regulator of the innate immune response. Nat Genet. 2009 Jul;41(7):829-32. doi: 10.1038/ng.373. Epub 2009 Jun 14. PMID:19525956 doi:10.1038/ng.373
↑ Ji X, Tang C, Zhao Q, Wang W, Xiong Y. Structural basis of cellular dNTP regulation by SAMHD1. Proc Natl Acad Sci U S A. 2014 Oct 14;111(41):E4305-14. doi:, 10.1073/pnas.1412289111. Epub 2014 Sep 29. PMID:25267621 doi:http://dx.doi.org/10.1073/pnas.1412289111

1 Structural highlights
2 Disease
3 Function
4 Publication Abstract from PubMed
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4to6"

@@ Line 1: / Line 1: @@
 ==Structure basis of cellular dNTP regulation, SAMHD1-dGTP-dATP-dTTP/dGTP complex==
 <StructureSection load='4to6' size='340' side='right' caption='[[4to6]], [[Resolution|resolution]] 2.33&Aring;' scene=''>
@@ Line 5: / Line 6: @@
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=DGT:2-DEOXYGUANOSINE-5-TRIPHOSPHATE'>DGT</scene>, <scene name='pdbligand=DTP:2-DEOXYADENOSINE+5-TRIPHOSPHATE'>DTP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=TTP:THYMIDINE-5-TRIPHOSPHATE'>TTP</scene></td></tr>
 <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4tnp|4tnp]], [[4tnr|4tnr]], [[4tnq|4tnq]], [[4tnx|4tnx]], [[4tny|4tny]], [[4tnz|4tnz]], [[4to0|4to0]], [[4to1|4to1]], [[4to2|4to2]], [[4to3|4to3]], [[4to4|4to4]], [[4to5|4to5]]</td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4to6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4to6 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4to6 RCSB], [http://www.ebi.ac.uk/pdbsum/4to6 PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4to6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4to6 OCA], [http://pdbe.org/4to6 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4to6 RCSB], [http://www.ebi.ac.uk/pdbsum/4to6 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4to6 ProSAT]</span></td></tr>
 </table>
 == Disease ==
@@ Line 19: / Line 20: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 4to6" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

4to6

From Proteopedia

Revision as of 19:38, 11 August 2016

Structure basis of cellular dNTP regulation, SAMHD1-dGTP-dATP-dTTP/dGTP complex

Structural highlights

Disease

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox